In the conventional storage system, there is a configuration where a parent storage device is arranged at a master site, and a child storage device for saving backup data is arranged at a remote site. By use of an internal volume copy function (volume copy function), an external connection function (function for communication connection with an external child storage device), and a LUSE (Logical Unit Number Size Expansion) function and the like that the parent storage device has, a remote backup system (function) may be configured (FIG. 15).
In the above configuration, consider that when the parent storage device is damaged due to a disaster for the master site, backup data (secondary volume data) stored in the child storage device at the remote site side is retrieved. Herein, the backup data may be stored separately in a plurality of storage volumes (logic units or the like) in one child storage device or more. In this case, even if it is tried to retrieve the backup data in the child storage device from, for example, a host device at the remote site, it is not possible to retrieve the data of the plurality of volumes (logic units or the like) that configure the child storage device, as a continuous single unit of data. This is because, at the remote site side, the volumes and the data groups are not controlled as one backup volume, and so forth. In the above case, in order to retrieve the backup data at the remote site side normally, for example, it is necessary to prepare (connect) a substitutional parent storage device, and recover the original configuration manually and so forth, which takes much time and labor.
Further, in the above configuration, in the case where data is transferred from an old storage device (parent) to a new storage device (child), it takes much time and labor (FIG. 16, FIG. 17).
For example, in Japanese Patent Application Laid-Open Publication No. 2005-11277 (Patent Document 1), a storage device to be connected to an external storage is disclosed.